Ken Done of weatherpredict.com seems to make a correlation for eruptions at the new moon.Aug 1-3. Also over Iceland there will be a planetary alignment on Aug15-17th.
At these times there will be increased gravitational pull on the earths crust.
Whether the eruption that is trying to happens occurs at these times or shortly after when the crust settles back after being stretched is anyones best guess.
Katla seems to have large frostquake activity after the subglacial eruption of last week.
The sub glacial pressure seems to have forced out meltwater hence the following glacier flood.
After some restive periods it seems the swarms have resumed in a more concentrated fashion and at larger periods.
The deformation between Eya and Katla seems to have stopped.
My bet would be for an increased chance of an event Aug 5th+/- 3days or Aug 17th+/-3 days.